8 Replies Latest reply on Sep 13, 2007 1:24 AM by Ramón G Castañeda

    ACR use of workdisk and scratchdisk when batch processing images

    gurglamei
      I am setting up a new PC optimized for PS, and I and pondering on the optimal disk setup for ACR when I batch process several images:

      Alternative 1
      2 physical disk in raid 0 with 2 partitions, partition 1 for scratch and the second for images to work on.

      The question is if there ever will be a conflict in the sence that PS/ACR wants to access both scratch- and work partitions at the same time? If this should occure, I guess the following is a better setup??:

      Alternative 2
      1 physical disk for scratch
      1 physical disk for images to work on

      Christopher
        • 1. Re: ACR use of workdisk and scratchdisk when batch processing images
          If you're concerned about speed, just make sure that ACR has enough RAM so that it *never* goes to the scratch disk -- then your problem becomes moot.

          RAM is cheap. Stuff your machine full of it.

          Kaa
          • 2. Re: ACR use of workdisk and scratchdisk when batch processing images
            Omke Oudeman Level 5
            I use a second internal disk (not the one with my system and application on it) with a seperate partition ( in my case 100 Gb but use at least 30 GB) as scratch disk and work at my files on my home disk ( you need at least 10 GB free space, otherwise it will slow down).

            I have 4 Gb RAM and have the default setting of percentage to use RAM.
            Don's forget to put the scratchdisk at first position in the prefs :-)

            I do work with layerd files of 150 mb and often have 20 or 30 them open om my desk top and work on them without problems and with a very good speed.

            See also this link from Adobe:

            http://kb.adobe.com/selfservice/viewContent.do?externalId=kb401089&sliceId=1
            • 3. Re: ACR use of workdisk and scratchdisk when batch processing images
              gurglamei Level 1
              Thanks to both of you, I appreciate your answers.

              However I still really haven got a full answer to the question if there ever will be a conflict in the sense that PS/ACR wants to access both scratch- and work partitions at the same time when batch processing images? If that is the case, it makes sense to have scratch and images on separate physical drives (or raids).

              I am planning on having 8 GB of RAM and a Q6700 CPU. I can have almost 10 disks, and I am pondering on the optimal system setup. Alternative 1 og 2??
              • 4. Re: ACR use of workdisk and scratchdisk when batch processing images
                Omke Oudeman Level 5
                Christopher,

                This is getting a little to technical for me but as far as I know working in PS or ACR uses RAM and if this is full it switches over to the scratchdisk. I always been told to use a scratchdisk that is a seperate physical disk other than the one your system and application is on.

                I'm not familiar with PC but by the sound of it I would say you have a fine work around.

                I switched from a dual processor 2 Ghz PPC to a 8 core Intel with 3 Ghz. With my 4 Gb RAM (slightly more than the previous Mac) converting a RAW file from my EOS 1Ds2 takes now only 2,5 seconds instead of 15 seconds, batching the layerd files (150 Mb) runs very smoothly and I'm afraid I don't have time for the coffee I used to take while waiting on the processing... :-)
                • 5. Re: ACR use of workdisk and scratchdisk when batch processing images
                  gurglamei Level 1
                  Thank's again Omke,

                  Maybe I am making this more of a problem than I really should. Your machine indeed seems quite capable and I gather mine will be too. However the computer geek part of me still would like to know what actually is optimal.... Prehaps I should just try it out once the computer arrives and find out for myself - but probably I won't bother once it set up and I can work on my pictures !

                  Christopher
                  • 6. Re: ACR use of workdisk and scratchdisk when batch processing images
                    Ramón G Castañeda Level 4
                    Alternative 2 is the way I'd go if I were limited to only two drives, one of them being the boot drive.

                    You don't want the OS and Photoshop competing for the use of the only read/write head on a single physical drive to write their swap and scratch disk files respectively. Partitioning does not solve the one-head only issue.

                    Photoshop ALWAYS uses a scratch disk. It creates one the instant you open a file or create a new document, its initial size being determined by assumptions Photoshop makes based on the nature of the file, layers, numbers of history states, etc., even your past workflow if there's enough of a record.
                    • 7. Re: ACR use of workdisk and scratchdisk when batch processing images
                      gurglamei Level 1
                      Thank you Ramón,

                      I am not limited to 2 drives. I am planning on having OS and programs on a third separate disk.

                      The point of using alternative 1 would be to use RAID 0 to obtain faster read/write (both for scratch and for reading and saving images on the work partition. However, if scratch usage competes with read/write to the work partition, I'm probably better off with alternative 2. If I work on one image this is simple, however I frequently batch process several RAW images. How does ACR/PS handle this? If all the images initially are read from the work partition and loaded into RAM + scratch and processed there, there will be no competition between the two partitions and I will benefit from the RAID solution. However, if the images are read one or just a few at a time, processed in RAM/scratch and then saved to the work partition, I imagine scratch and work partition could be competing for the the disks read/write head when finished images are being saved and ACR is "waiting" for more images to process??
                      • 8. Re: ACR use of workdisk and scratchdisk when batch processing images
                        Ramón G Castañeda Level 4
                        >I am not limited to 2 drives.

                        You're fine, then.

                        Sorry I can't offer you any assistance re how ACR handles batch processing. I assume you want to do it through Bridge (Bridge hosting ACR rather than Photoshop hosting ACR) so you won't run into the smaller limit mentioned elsewhere in this very same forum:

                        Jeff Schewe, "Cannot open NEF files from D200 in Camera Raw 4.1" #13, 12 Aug 2007 6:47 pm